1. Field of the Invention
The present invention relates to a method of predicting wear of a die surface, and more particularly to a method of predicting wear of a draw bead surface of a stamping die.
2. Background Art
Stamping operations are used to fabricate a variety of automotive components, such as vehicle body panels. A stamping operation may utilize one or more dies to form a part having a desired shape. Die surfaces, such as draw bead surfaces, are susceptible to wear due to high localized contact pressures and friction. Wear may result in an inability to maintain dimensional tolerances, reduced part surface quality, and further degradation to the die.
Previously, part or die surfaces were inspected to detect die surface wear. These inspection techniques detected wear after it occurred, thereby increasing scrap and reducing process efficiency. Moreover, inspection techniques rely on manual observations that are inherently subjective.
Before applicant's invention, a method was needed for predicting die wear. In addition, a method was needed that proactively predicted die wear so that preventive or corrective actions could be taken to extend die life and reduce downtime. In addition, a method was needed that could predict die wear before part quality was affected, thereby reducing scrap and surface quality issues. In addition, a method was needed that was compatible with various part materials, material geometries, die surface coatings, die geometries, and lubrication conditions. Problems associated with the prior art as noted above and other problems are addressed by applicants' invention as summarized below.